There is a large amount of buried cable in the world. Much of this cable includes valuable metals such as copper or the like, the price of which has in recent years increased substantially. Some of this buried copper cable has been left in the ground to be replaced by optical fibre. The buried cable has substantial value because of its copper content and is therefore highly desirable to remove as well as for environmental reasons.
Most of the buried copper cable has been left in the ground as there has nor been an effective way of removing substantial lengths of the cable. In some cases, attempts have been made to uncover the buried cable by digging a trench above the cable using trenching equipment and then in a separate operation digging down to the cable and lifting it out. Such system is labour intensive.
In other eases, attempts have been made to automate the location of the buried cable by using GPS systems or radio frequency means which have not been very effective. Furthermore, some of the prior art equipment and methods have lacked controllers which are designed to keep the trenching equipment substantially over the buried cable.
Furthermore, many of the prior art devices lack effective means for pulling out the buried cable without snapping or cutting of the cable. Finally, in some cases, the ground has been compacted to such an extent that the prior art devices and methods have been ineffective to produce efficient cost-effective removal of the buried cable.
Various prior art has heretofore been issued for a variety of devices, systems and methods relating to cable trenching.
For example U.S. Pat. No. 5,190,409 relates to a conventional cable-laying apparatus has been adapted for the removal of cable. A trenching plow blade is towed behind is bulldozer or the like. Mounted above the area of the blade is a powered cable-pulling assembly. Once an initial length of cable is excavated and routed to the cable pulling assembly, the equipment is advanced along the line of the cable to dig the trench, preferably just a small distance above the cable, such as about a foot, and the cable pulling assembly is driven to pull the cable from the ground behind the advanced blade. The cable may be routed to lie on the ground behind the advancing apparatus, or alternatively may be routed forward over the cab of the bulldozer onto a powered rewind reel. The cable pulling assembly includes a pulling wheel rotatably mounted to the blade support assembly, rotated by a hydraulic motor through to reduction gearbox. A series of rollers are mounted between two roller support arms. The roller support arms are connected to each other and pivotally mounted at one end to the blade support assembly to rotate around a pivot pin. A hydraulic cylinder mounted between the blade support assembly and the roller support arms is operable to move the roller support arms to a closed position in which the rollers force the cable into the grooved portion of the pulling wheel, where teeth defined by the edges of squares rods into the cable to grip it securely for pulling.
Also U.S. Pat. No. 8,209,136 shows a line locator includes a signal detector to detect signals from an underground line; an error modeler that models a phase error in the signal from neighboring underground lines; and an enhanced electromagnetic field modeler that provides a location of the underground line based on the signal and a result from the error modeler.
Moreover U.S. Pat. No. 5,741,088 relates to an excavation apparatus comprising: a wedge member for driving through the ground and for slidingly contacting and lifting an overburden located beneath the surface of the ground substantially toward the surface of the ground; a driving attachment member for driving the wedge member below and substantially parallel to the surface of the ground; and a lateral support member attached to the wedge member for guiding the overburden across the wedge member. The apparatus may remove an existing utility line, install a new utility line, apply bedding material beneath a new utility line, or form as trench.
Furthermore U.S. Pat. No. 4,014,175 relates to a cable and pipe laying machine.
U.S. Pat. No. 6,633,163 B2 teaches an excavator vehicle has sensors thereon at different heights. Each sensor may have a coil which is generally horizontal and which detects the magnetic field generated by a current in a buried conductor. By detecting the relative magnitudes of the component of the field parallel to the ground, as detected by the sensors, it is possible to determine whether or not the excavator vehicle is proximate the buried conductor. A warning may be generated, or the excavating tool of the excavator vehicle controlled, to prevent the excavating tool damaging the buried conductor.
U.S. Pat. No. 7,038,454 B2 shows a system and method for detecting an underground object using magnetic field sensing.
Furthermore U.S. Pat. No. 7,759,824 B2 teaches a system and method use magnetic field sensing to detect underground objects for strike avoidance. The system detects magnetic field components for both passive distortions in the magnetic field indicative of a ferromagnetic object and active magnetic fields that are impressed on an object by a signal generator.
Moreover U.S. Pat. No. 5,949,373 relates to a method for accurately locating buried utility conveyance, comprising the step of: burying the conveyance while making at least one global positioning satellite location measurement of the location of the conveyance during burial.
U.S. Pat. No. 4,430,022 shows an underground cable installing apparatus and method utilizing a multi-positionable plow blade
Finally U.S. Pat. No. 5,215,868 related to an apparatus for laying an underground member
It is an object of this invention to provide a more efficient trench plow blade for removing a cable below ground. Furthermore, it is another object of this invention to provide more efficient apparatus and systems for removal of the cable buried in the ground including a method for removing buried cable in the ground with a trench plow blade.
It is an aspect of this invention to provide a trench plow blade for removing cable below ground, comprising: a plow member having an upper end and a lower end where the upper end is adapted to be disposed above ground and the lower end adapted to be disposed below ground; a plow wedge disposed at said lower end and adapted to lift the ground above the cable when the trench plow blade is moved through the ground. By lifting the over burden, the width of the plow wedge box allows for a greater margin of error.
It is another aspect of this invention to provide apparatus for the removal of cable buried in the ground comprising: a blade support assembly; a trenching plow blade suspended from the blade support assembly; structure for moving the blade support assembly and said trenching plow blade through the ground above the cable; structure for orienting said trenching plow blade in the ground substantially over said cable; radio frequency means for transmitting a signal to said buried cable, and for receiving a locate signal; microprocessing means communicating with said radio frequency means so as to communicate with said orienting means to orient said trenching plow blade in the ground substantially over said cable; pulling means for pulling cable removed from said ground as the moving structure moves the blade assembly and trenching plow blade through the ground above the cable, said pulling means communicating with said radio frequency means and said pulling means including means for piercing said cable to contact the metal in said cable so that said radio frequency means produces a locate signal in said buried cables.
Yet another aspect of this invention relates to it method removing buried cable in the ground with the trenching plow blade comprising: loosening the ground above the buried cable; moving said trenching plow blade through the around above the buried cable; pulling the buried cable out of the ground.
These and other objects and features will now be described in relation to the following drawings.